What size heater?

[Saaqib_Ansari]

Guys I need a hand with what size heater to put into my tank. I have a 650L tank with a 150L sump. What watt heater do I need? Every conversion website I find keeps saying it in gallons and I’m not sure if it’s uk or US gallons.
Also would I only be heating the water in the sump or do I have to account for the entire water body.
Thanks

 

[oscarjinjer]

Good question but entire water column, 800 litres at minimum 300 watts.

 

[Saaqib_Ansari]

Good question but entire water column, 800 litres at minimum 300 watts.

dang I thought they only go to 100W max per heater? So would I need 3 of those in my sump?

 

[Fish E]

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Aquarium Heaters: What you need to know! | BeanAnimal's Reef